The prognosis of a disease or pathological condition in a subject can be greatly improved with an early diagnosis. However, reliable prognostic and diagnostic methods are lacking for managing disease states. For example, for Alzheimer's disease, the only definitive diagnostic test is to determine whether amyloid plaques are present in a subject's brain tissue, a determination that can only be made after death. Thus, due to the lack of suitable diagnostic methods only a tentative diagnosis can be provided. In another example, diagnosis and prognosis of a cancer are important for choosing the best treatment options in order to improve outcome. There is also a need for diagnostic and prognostic tests to predict the efficacy of a particular chemotherapy regime to determine the best treatment options for a subject.
Therefore, there is a significant need in the art for more accurate and reliable diagnostic and prognostic methods for cancer and Alzheimer's disease.